resource "aws_security_group" "k8s-node" {
  name        = "k8s-node"
  description = "Kubernetes Node"

  egress {
    from_port        = 19998
    to_port          = 19998
    protocol         = "udp"
    cidr_blocks      = ["0.0.0.0/0"]
    ipv6_cidr_blocks = ["::/0"]
  }

  egress {
    from_port        = 443
    to_port          = 443
    protocol         = "tcp"
    cidr_blocks      = ["0.0.0.0/0"]
    ipv6_cidr_blocks = ["::/0"]
  }

  egress {
    from_port        = 80
    to_port          = 80
    protocol         = "tcp"
    cidr_blocks      = ["0.0.0.0/0"]
    ipv6_cidr_blocks = ["::/0"]
  }
}

resource "aws_launch_template" "k8s-aarch64" {
  name = "k8s-aarch64"

  update_default_version = true
  image_id               = "ami-000ec96ccb51eb679"
  instance_type          = "t4g.medium"
  security_group_names   = [aws_security_group.k8s-node.name]

  user_data = filebase64("${path.module}/userdata.yml")

  instance_market_options {
    market_type = "spot"
  }

  private_dns_name_options {
    hostname_type = "resource-name"
  }
}

resource "aws_autoscaling_group" "k8s-aarch64" {
  name = "k8s-aarch64"

  availability_zones = ["us-east-2a", "us-east-2b", "us-east-2c"]
  min_size           = 0
  max_size           = 1

  launch_template {
    id      = aws_launch_template.k8s-aarch64.id
    version = "$Latest"
  }

  tag {
    key                 = "k8s.io/cluster-autoscaler/enabled"
    value               = "true"
    propagate_at_launch = true
  }
  tag {
    key                 = "k8s.io/cluster-autoscaler/kubernetes"
    value               = "owned"
    propagate_at_launch = true
  }
}